实验研究了近红外可调谐激光二极管吸收光谱技术(TDLAS)在气体监测中的应用,提出了在一种应用于煤矿瓦斯监测的光纤传感方法。该方法基于气体近红外波段的特征吸收,通过对窄线宽分布式反馈(DFB)激光器进行波长调制,并采用谐波检测技术,消除了光源波动和光纤抖动造成的影响,提高了瓦斯气体的测量灵敏度。同时,采用空分复用(SDM)技术组成光纤传感网络,提出了一种能实现在线监测的多点瓦斯传感系统,该方法降低了系统成本,能适应煤矿等恶劣环境的应用需求。 The application of Near Infrared Tunable Laser Diode Absorption Spectroscopy (TDLAS) in gas monitoring was experimentally studied, and an optical fiber sensing method for gas monitoring in coal mine was proposed. The method is based on the characteristic absorption of the gas near-infrared band, and by wavelength modulation of a narrow linewidth distributed feedback (DFB) laser and harmonic detection technology, the influence of light source fluctuations and optical fiber jitter is eliminated, Measurement sensitivity. At the same time, the air sensing system is composed of SDM technology. A multi-point gas sensor system is proposed to realize on-line monitoring. This method can reduce the system cost and meet the application requirements of harsh environments such as coal mines.